Multicolor negative film with integral masking images



Feb. 24, 1953 H. H. DUERR ETAL MULTICOLOR NEGATIVE FILM WITH INTEGRAL MASKING IMAGES Original Filed May 3, 1944 Blue Sensitive Yellow Filter Exposure l e y D 0 Z A W m H VI 6 V m S n e S Red Azo Dye Base Negative Color Development Color Negative Negative Color Images and Negative Silver Silver Dye Bleach Treatment r Yellow Masking Positive Red Masking Positive -Base rm wwm w. f"? z m .N R cw o MWMN W www A H m H Patented Feb. 24, 1953 UNITED STATES PATENT OFFICE MULTICOLOR NEGATIVE FILM INTE- GRAL MASKING IMAGES Herman H. Duerr, Herbert W. Morreall, Jr., and Harold C. Harsh, Binghamton, N. Y., assignors 'to- General Aniline & Film Corporation, New York, N. Y., a. corporation of Delaware Original application May 3, 1944, Serial No. 533,833, now Patent No. 2,464,798, dated March 22, 1949. Divided and this application March 5, 1946, Serial No. 652,250

1 Claim.

This application relates to color photography and particularly to color negatives containing integral masking images for color correction purposes. It is a division of our copending application Serial No. 533,833, filed May 3, 19414:, now Patent No. Z/lfidflQS.

Iii the production oi. color prints or color transparencies from natural order color negatives, the multilayer color negative consists of yellow, magenta and cyan images in three different layers; the cyan image represents the red, the magenta image the green and the yellow image the blue record of the original subject. Color positive prints or transparencies may be obtained from such color negatives by direct pensate for the incorrect color absorption of the printing on a multilayer color positive film or cyan and magenta dyes. We have now found paper or by making color separation negatives that another method for integral masking can be which are then used for the making of color used for multilayer color negative films with or positive prints. n Without color coupling components in the in- It is known that the colors, pigments or inks dividual emulsion layers which also has definite which are used in color photography for formadvantages over the known methods of color coring the transparent dye images are not ideal in rection. The masks according to this method their absorption characteristics for allowing are produced within the individual layers of the color reproductions which are perfectly true in color negative material itself, thereby obviating their color hues. Variousways and means have any dimculties of registration. This new method been devised to correct ior the imperfect absorpof color correction is simple and self-controlling tion of the dyes which are used. Generally-it in operation. has not been very difiicul-t to find suitable yellow The invention will be more readily understood dyes or pigments which have acceptable absorpwhen read in connection with the accompanying tion characteristics and therefore images of such drawing, the single figure of which shows a flow dyes need no correction in color printing proodiagram of the color negative exposure and esses. The ma e ta dy s, owev sp y development procedure which results in the color those which are obtained'by color-forming deVo1 corrected or masked color negative transparency. opment, and the cyan dyes do not have these The flow diagram shows three cross-sections of desirable absorption characteristics. The mathe film labeled A, B, and C, respectively, each genta dyes, pigments i y have ve y indicating a step in the process. undesirable absorption in the blue and in many The first step, A, shows the condition of the cases incomplete absorption in the green region; film. as it is being exposed. he yan dyes usually ShOW a C ns a le a The second step, B, shows the condition of the 5 M in the b e a d green leg o T0 40 exposed film after it has been treated for negpensate for these deficiencies in the absorption tiv color development or the magenta andcy dyes n 0 negatives, The third step, C, shows the condition of the it is necessary to apply color correction or maskexposed and color developed film after it has ing methods in order to obtain color prints with been submitted to a silver dye bleach treatment. true tonal values. Referring to the drawings and particularly to One well known method of Obta such step A thereof, it willbe seen that the original color correction consists in making a'woak DO material comprises a base, 5, upon which are itive from one color record and sup rimp sin superimposed three silver halide emulsion layers, this positive mask th a S c 01 reco d one of which, indicated by the numeral i, is red when printing from the latter record. In this so sensitive; another of which, indicated by the case an additional film and printing operation numeral 2, is green sensitive; and a third of are necessary to provide the color correction which, indicated by the numeral 4, is blue senmask. Furthermore, the problem, of securing sitive. .On top of the, green sensitive or so-called the proper registration of the two images. makes magenta layer there is a gelatine filter layer this method complicated. It has also been pro- Econtaining colloidal silver or a fogged emulsion posed to incorporate in a multilayer film containing color forming components a separate emulsion layer and to convert this separate layer by special and complicated processing steps into a masking layer.

In our Patent No. 2,357,388, we have described a process wherein the difiiculties and. disadvantages attendant upon the use of known processes and known color negatives containing color images can be overcome by producing only in the cyan and magenta layers of negative subtractively colored multilayer film so called positive rest images or stained images and utilizing'these images as masks in printing to comcontaining a yellow azo dye which can be destroyed in the presence of silver in a dye-silver bleaching bath. Suitable yellow azo dyestuffs for this purpose would be, for instance, Fastusol Yellow LRA (Benzo Fast Yellow RL, 0. I. 349 A). Suitable colloidal silver filter layers are disclosed in U. S. P. 2,220,187.

The red sensitive layer, layer I, may contain a non-diffusing color coupling component capable of being developed to a cyan dye image with a color developer comprising an aromatic amino developing agent such as diethyl-para-phenylamine-diamine. We have found that suitable cyan dye images may be produced from the color components disclosed in U. S. P. 2,179,238, 2,186,733 and 2,224,329. Specific examples of such color components are, for instance, 3.5-di- (phenylamino)phenol, abietyl-amino-naphthol, 1-N-stearyl-4-N-(1 hydroxy 2' naphthoyl) phenylene-diamine sodium sulfonate and the like. The green sensitive layer 2 may contain a color coupling component capable of forming a magenta dye with a suitable color developer as above. Satisfactory color components for the magenta image are the non-difiusing components described in U. S. Patents 2,178,612 and 2,179,238. Examples of such components are the condensation product of meta-amino-phenyl-methyl-pyrazolone and the mixed polymer of vinyl chloride and maleic acid anhydride, llmyristyl amino 2- sulfolphenyl-3-methyl-5-pyrazolone, and the like. The blue sensitive layer 4 contains a color coupling component capable of forming a yellow dye image with a color developer as above. Satisfactory components for this layer are the nondifiusing yellow color components described in U. S. Patents 2,179,238 and 2,224,329, examples of which are terephthaloyl-bisacetic acid anilidep'-carboxylic acid, and the like.

The multilayer film of the figure having the cyan, magenta and yellow color components in the respective layers I, 2 and 4, is treated so as to produce a yellow or red azo dye masking image in the cyan layer and a yellow azo dye masking image in the magenta layer. This is accomplished by incorporating a red azo dye of low color density in the cyan layer and a yellow azo dye of low color density in the magenta layer when the film is being made. The yellow and red azo dyes which are so used in the magenta and cyan layers preferably should be substantive to gelatine or contain groups so that they can be precipitated with precipitating agents such as calcium lactate and diphenyl-guanidine or p-naphthyl-bi-guanide so as to make them non-diffusing. These azo dyes must also be capable of being destroyed by a suitable bleach bath in the presence of silver, for instance, thiourea in acid solution. Azo dyes suitable for this purpose are, for instance, Walk Yellow 0, Xylen Walk Yellow, Fastusol Yellow L. R. A. (C. I. 349 A), Extra, Brilliant Purpurine (Schultz 423, 1931, 7th edition), Supranol Brilliant Red B, Congo Red (Schultz 360), Cotton Red 4B (Schultz 448), and Direct Red (Schultz 439).

A preferred method of processing the film in order to obtain a suitable integral masking image in the multicolor negative described above wherein the azo dyes are incorporated in the cyan and magenta layers is as follows:

After exposure to a colored subject of a multilayer color negative film containing the color coupling components in the cyan, magenta and yellow layers l, 2 and 4, respectively, the film is color developed in a color developer, for instance,

a diethyl-para phenylene-diamine developer such as one of the following composition:

Grams Sodium sulfite 1 Diethylpara-phenylene-diamine 2 Sodium carbonate 50 Potassium bromide 2 Water to make 1000 cc.

This color development produces the negative color image illustrated in the drawing step 13. Referring to said step B, the top layer 4 contains at this step a yellow colored negative image together with a negative silver image, the filter layer 3 has not been affected in the case where a layer of colloidal silver dispersed in gelatin has been used. If a fogged emulsion containing a yellow azo dye has been used for the filter, this layer would contain a uniform silver deposit together with a uniformly distributed yellow azo dye. The magenta layer 2 contains the uniformly distributed yellow azo dye in low concentration plus a magenta colored negative image in situ with a negative silver image. The cyan layer I contains a uniformly distributed red azo dye in low concentration plus a cyan colored negative image in situ with a negative silver image. The film is now fixed and washed by the usual methods. It is then treated in a silver dye bleach bath which has no irreversible effect upon azo methine or quinone imine dyes produced by color development. Acid thiourea and potassium thiocyanate baths, of which the following are typical examples, have been found suitable for this purpose:

l hiourea gms Citric lcid gms Water to make cc 1, 000 l, 030

Similar silver dye bleach baths may be substituted which contain, in place of the thiourea or potassium thiocyanate, any nitrogen compound containing a thioketo group which is water soluble or can be water solubilized. Further examples of such compounds are: rhodanine, thiohydantoin, thiourazole, and thiotetrazoline. Any water soluble inorganic thiocyanate and thiourea-dioxide may also be used.

The yellow azo dyestuff in the magenta layer 2 and the red azo dyestuff in the cyan layer 1 are destroyed in situ with the negative silver in said magenta and cyan layers by the silver dye bleach bath. The negative color images which have been produced by color-forming development are little if any affected by the acid thiourea bath. In case the color densities of these color images, however, have been decreased by the acid, the color can be brought back by a short rinse in a diluted sodium carbonate solution.

The azo dyes in the cyan and magenta layers are bleached out proportionally in all places where negative silver has been developed in the original color development and masking positive dye images of low density are formed in these two layers. The drawing step C illustrates the condition of the layers at this stage of the procedure. The dotted areas in layers l and 2 represent the yellow and red positive masking images in the magenta and cyan layers respectively. The contrast of these masking images is controlled by the bleaching time in the acid thiourea silver-dye bleach bath and by the original azo dye concentration in the layers. The residue of negative silver contained in the layers can be bleached out in a regular ferricyanide bleach bath such as one of the following composition:

Potassium f-erricyanide, grams Water to make 1000 cc.

Finally the film is fixed in a standard fixing bath of for instance 10% hypo.

The following example will serve to further illustrate our invention, it being understood that the invention is not limited thereto. Except as otherwise noted, the parts are by weight.

Example To 1000 cc. of a panchromatic-sensitized silver halide emulsion, 10 grams of the cyan color former l-N-stearyl 4 N (1-hydroxy2-naphthoyl) phenylenediamine sulfonic acid sodium salt are added. In addition to the color former 0.4 gram of Congo red is added to the emulsion. The emulsion is coated on a support producing a dry emulsion thickness of approximately 6 to 8 mu. A green-sensitive emulsion layer containing 1[myristyl amino 2 sulfolphenyl 3 methyl-5- pyrazolone as a non-difiusing magenta color component is coated on top of a cyan layer. This layer, in addition to the non-diifusing magenta color component, contains 0.6 gram of Fastusol Yellow L. R. A. (C. I. 349 A). A yellow filter layer and blue sensitive emulsion layer containing terephthaloyl-bisacetic acid anilide-p-carboxylic acid as a non-difiusing color component for yellow are then coated on the green-sensitive emulsion layer. After exposure and color development for approximately 10 minutes at 70 F. in the following color developer:

Grams Diethyl paraphenylenediamine hydrochloride 3 Sodium carbonate, monohydrate 50 Potassium bromide 2 Water to make 1000 co.

the film is fixed in a fixing bath of the following concentration:

Sodium thiosulfate, 100 grams Water to make 1000 cc.

The film now contains a cyan image in the panchromatic bottom layer in situ with the negative silver image and a magenta image in the green-sensitive emulsion layer also in situ with the negative silver image. In addition to the cyan and magenta images, these layers are uniformly colored red and yellow respectively by the Congo Red and Fastusol Yellow dyes added thereto. The positive red masldng image in the cyan layer and the positive yellow masking image in the magenta layer are now formed by bleaching the respective red and yellow azo dyes in situ with the negative silver image by treating the film in an acid thiourea bath in the concentration No. I of the table in column 4. The red azo dye in the cyan layer and the yellow azo dye in the magenta layer will be bleached out in proportion to the density of the negative silver and a low density positive red masking image is formed in the cyan layer and a low density positive yellow masking image in the magenta layer.

Various modifications of this invention will occur to persons skilled in the art and it is, therefore, understood that we do not intend to be limited in the patent granted except as required by the claim.

We claim:

Subtractively colored multilayer transparent negatives suitable for printing comprising a base and three layers superimposed thereon, said layers containing in the innermost layer transparent cyan negative images, in the next adjacent layer transparent magenta negative images and in the outermost layer transparent yellow negative images and containing in the cyan layer red azo dye positive images of low color density and in the magenta, layer yellow azo dye positive images of low color density.

HERMAN H. DUERR. HERBERT W. MORREALL, JR. HAROLD C. HARSH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,193,931 Michaelis Mar. 19, 1940 2,252,718 Mannes et al Aug. 19, 1941 2,449,966 Hanson Sept. 21, 1948 FOREIGN PATENTS Number Country Date 512,608 Great Britain Sept. 21, 1939 541,266 Great Britain Nov. 20, 1941 

